Air conditioning system

ABSTRACT

An air-conditioning system contains an evaporator housing having an air inlet, an air outlet, and an inner space formed therein. An air-through flow evaporator is disposed in the evaporator housing. At least one injection device is supported by the evaporator housing and is directed into the inner space. A supply line is connected to the injection device, and through the supply line and the injection device a cleaning agent and/or a disinfecting agent is injected into the evaporator housing.

BACKGROUND OF THE INVENTION

[0001] Field of the Invention

[0002] The invention relates to an air conditioning system, inparticular for a motor vehicle, with a refrigerant conveyed in a closedcircuit and with an evaporator housing having an air inlet, an airoutlet, an inner space and an air-through flow evaporator disposed onthe latter.

[0003] Air conditioning systems, in particular those for motor vehicles,with a refrigerant conveyed in a closed circuit and with an evaporatorhousing having an air inlet, an air outlet, an inner space and anair-throughflow evaporator disposed in the latter, are known in manydifferent forms of construction.

[0004] Such air conditioning systems have the disadvantage that theiroften highly fissured inner space is accessible only with greatdifficulty, if at all, but that microbes or fungal cultures colonize, inparticular, in the evaporator and the air guide ducts surrounding thelatter and located downstream in the direction of flow and may flourishuninhibitedly there. This results in that the interior climate in apassenger space is appreciably impaired or even becomes hazardous tohealth, since fungal spores and other impurities are conveyed directlyinto the passenger space by the cooling-air stream.

[0005] So that such impurities can be eliminated, it is necessary, as arule, to open the evaporator housing of an air conditioning system andclean it by a cleaning and/or disinfecting agent, but this is highlylabor-intensive and therefore costly, so that this maintenance work onan air conditioning system is often neglected for reasons of cost, thisalso being detrimental to the satisfactory functioning of the airconditioning system. Owing to the highly fissured inner space, suchcleaning often cannot be carried out very thoroughly, with the resultthat the entire cleaning process is of little effectiveness.

SUMMARY OF THE INVENTION

[0006] It is accordingly an object of the invention to provide an airconditioning system that overcomes the above-mentioned disadvantages ofthe prior art devices of this general type, which can be maintained inan optimum operating state in a simple and cost-effective way.

[0007] With the foregoing and other objects in view there is provided,in accordance with the invention, an air-conditioning system. Theair-conditioning system contains an evaporator housing having an airinlet, an air outlet, and an inner space. An air-through flow evaporatoris disposed in the evaporator housing. At least one injection device issupported by the evaporator housing and directed into the inner space. Asupply line is connected to the injection device, and through the supplyline and the injection device a cleaning agent and/or a disinfectingagent is injected into the evaporator housing.

[0008] What is achieved by the fact that the at least one injectiondevice directed into the inner space of the evaporator housing isdisposed on the latter, and the injection device being connected to asupply line through which the cleaning and/or disinfecting agent can beinjected into the evaporator housing, is that the evaporator housing nolonger has to be dismantled in order to clean the air conditioningsystem. The result is that the work becomes vastly easier and can becarried out quickly, efficiently and cost-effectively, thus alsoaffording the advantage that the cleaning frequency of the airconditioning system can be increased markedly, without cleaning being anappreciable cost factor in the maintenance of the motor vehicle.

[0009] The cleaning itself in this case takes place, as is customary,when the engine and the air conditioning system are at a standstill,after which, when the cleaning and/or disinfecting agent has beeninjected, a relatively long active time and vaporization time have to beadhered to, whereupon the air conditioning system can be put intooperation again immediately.

[0010] In a particularly preferred embodiment of the invention, theinjection device formed of the supply line which is led from outsideinto the evaporator housing and which is provided, within the evaporatorhousing, with outlet orifices for the cleaning agent which may consist,for example, of simple pierced holes introduced into the supply line.Such an embodiment of an injection device is extremely cost-effectiveand is also particularly advantageous because the regions of the supplyline that are provided with the outlet orifices can be matched optimallyto the contour of the evaporator housing. Furthermore, using T-pieces orother connectors, a division of the supply lines into two or moreinjection devices can be carried out.

[0011] According to another preferred embodiment of the subject of theinvention, the injection device contains separate nozzles that extendthrough the wall of the evaporator housing and are connected to a commonsupply line. It thereby becomes possible to select nozzles with adefined injection angle and predeterminable injection quantity andinjection quality, so that the cleaning result is further improved, ifappropriate along with a minimized use of cleaning or disinfectingagents.

[0012] It is also advantageous if a plurality of injection devices aredisposed upstream and also downstream of the evaporator in a conveyingdirection of the air. A configuration in the upper region of theevaporator housing being appropriate, since the cleaning agents can thenrun slowly downward, exerting their cleaning action, as a consequence ofgravity and by virtue of their adhesion along the inner surface of theevaporator housing and of the evaporator, and in the meantime evaporate,so that a further optimized cleaning result can be achieved.

[0013] According to a particularly preferred embodiment of theinvention, the injection direction of some of the outlet orifices ornozzles is oriented such that the cleaning and disinfecting agents areconveyed through the evaporator in parallel with a direction of flow ofthe air through the latter, thus making it possible to ensure that theentire large surface of the evaporator and the inner walls of theevaporator housing and of the cooling-air feed lines are wetted by thecleaning agent.

[0014] In order to ensure that even regions downstream of the evaporatorhousing undergo sufficient cleaning, part of the injection device may belocated in the region of the air outlet of the evaporator housing in thedirection of flow of the cooled air, so that fungal cultures locatedthere are likewise killed.

[0015] It is particularly advantageous, furthermore, that a couplingpiece is provided on the supply line for the connection of acleaning-agent feed, so that the latter can be connected without majoroutlay to the air conditioning system, without the use of tools becomingnecessary.

[0016] Furthermore, particular importance is attached to an embodimentof the air conditioning system in which a reservoir for a cleaning agentis permanently connected via an activatable switching valve to thesupply line of the injection device. The switching valve being actuablemanually, semi-automatically or fully automatically via an electroniccontrol, so that cleaning or disinfection of the air conditioning systemmay be carried out not necessarily solely during a workshop visit, butmay be carried out at regular time intervals or as a function of theactual operating hours, when it is ensured that the vehicle is not putinto operation again for a minimum period of time after the cleaning hasbeen carried out.

[0017] It is advantageous, furthermore, for the injection device to beconfigured as a retrofitting kit, so that even older air conditioningsystems can be equipped with it.

[0018] Other features which are considered as characteristic for theinvention are set forth in the appended claims.

[0019] Although the invention is illustrated and described herein asembodied in an air conditioning system, it is nevertheless not intendedto be limited to the details shown, since various modifications andstructural changes may be made therein without departing from the spiritof the invention and within the scope and range of equivalents of theclaims.

[0020] The construction and method of operation of the invention,however, together with additional objects and advantages thereof will bebest understood from the following description of specific embodimentswhen read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021]FIG. 1 is a diagrammatic, side sectional view of an evaporatorhousing according to the invention;

[0022]FIG. 2 is a top, sectional view of the evaporator housing of FIG.1;

[0023]FIG. 3 is a side-elevational view of the evaporator housing with avariation of the injection device;

[0024]FIG. 4 is a top, sectional view of the evaporator housing shown inFIG. 3; and

[0025]FIG. 5 is a top, sectional view of a further evaporator housingwith an injection device integrated into an evaporator.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Referring now to the figures of the drawing in detail and first,particularly, to FIG. 1 thereof, there is shown a part of anconditioning system, in particular one for motor vehicles, and operated,as a rule, with a refrigerant which is circulated in a circuit and whichis expanded in a heat exchanger configured as an air-through flowevaporator 2 and evaporates, and at the same time absorbing heat fromthe air supplied.

[0027] An evaporator housing 1 has a free inner space 3, in which theevaporator 2 is disposed in such a way that the inner space 3 is dividedinto two separate spaces. Furthermore, the evaporator housing 1 has anair inlet 9 and an air outlet 10, to which is connected a cooling-airduct 11, through which the cooled air is conveyed into the passengerspace of a motor vehicle.

[0028] As illustrated in FIGS. 1 and 2, the inner space 3 of theevaporator housing 1 has provided in it, on each side of the evaporator2, a hose-like injection device 4 which is provided with simple outletorifices 7 which are configured as holes but which are directed into theinner space 3 preferably toward the evaporator 2, so that cleaning anddisinfecting agents 13 can wet the entire surface of the evaporator 2 oflamellar construction, before they have vaporized. The configuration ofthe injection device 4 as a hose or thin tube makes it possible to matchit to the often highly complex contour of the evaporator housing 1, sothat it can be disposed in the evaporator housing 1 extremelyeffectively, and to cause little obstruction to the air stream.

[0029] A second embodiment, such as illustrated in FIGS. 3 and 4, has aninjection device 5 possessing separate nozzles 8 which are disposed, forexample, in the wall of the evaporator housing 1 and are connected to acommon supply line 6. The configuration of the nozzles 8 does notnecessarily have to take place in the wall of the evaporator housing 1,but may be carried out at any desired point within the evaporatorhousing 1, for example on separate fastening brackets or directly on theevaporator 2.

[0030] The embodiment of the injection device 5 with the nozzles 8 makesit possible also to utilize the pressure or the outlet velocity of thecleaning and disinfecting agent in order to improve the cleaning result.Furthermore, individual nozzles 8 can also be used in the region of theair outlet 10 of the evaporator housing 1 with an outflow direction inthe direction of the cooling-air duct 11 or else directly into this, sothat the cooling-air ducts 11, too, can be cleaned, at least as far astheir first branch, by the cleaning and disinfecting agent.

[0031] As illustrated in FIG. 5, the injection device 5 may also beintegrated in the evaporator 2, so that an optimum cleaning action canbe achieved.

[0032] A coupling piece 12 for the connection of a cleaning-agent feedis provided on the supply line 6, a reservoir 15 for the cleaning agent13 being capable of being permanently connected to the supply line 6 viaan activatable switching valve 14, the switching valve 14 being actuablemanually, semiautomatically or fully automatically via an electroniccontrol 16 (see FIG. 3), the latter being capable of being used, forexample in terms of a maximum operating time of the air conditioningsystem, a maximum time lapse or a traveling distance covered, as a pulsegenerator for putting the injection device 4, 5 into operation.

We claim:
 1. An air-conditioning system, comprising: an evaporatorhousing having an air inlet, an air outlet, and an inner space formedtherein; an air-through flow evaporator disposed in said evaporatorhousing; at least one injection device supported by said evaporatorhousing and directed into said inner space; and a supply line connectedto said injection device, and through said supply line and saidinjection device at least one agent selected from the group consistingof a cleaning agent and a disinfecting agent being injected into saidevaporator housing.
 2. The air conditioning system according to claim 1,wherein said injection device includes said supply line and said supplyline is introduced into said evaporator housing from outside, saidsupply line, within said evaporator housing, having outlet orificesformed therein for the agent.
 3. The air conditioning system accordingto claim 1, wherein said injection device includes a plurality ofseparate nozzles connected to said supply line.
 4. The air conditioningsystem according to claim 1, wherein said injection device is one of aplurality of injection devices disposed upstream and downstream of saidair-through flow evaporator in a conveying direction of air.
 5. The airconditioning system according to claim 1, wherein said evaporatorhousing has an upper region, and said injection device is disposed insaid upper region.
 6. The air conditioning system according to claim 1,wherein said injection device is integrated in said air-through flowevaporator.
 7. The air conditioning system according to claim 2, whereinan injection direction of some of said outlet orifices is orientedparallel to a main direction of flow of air through said air-throughflow evaporator.
 8. The air conditioning system according to claim 3,wherein an injection direction of some of said nozzles is orientedparallel to a main direction of flow of air through said air-throughflow evaporator.
 9. The air conditioning system according to claim 2,wherein at least one of said outlet orifices is disposed in a region ofsaid air outlet of said evaporator housing so that the agent can beinjected in a direction of flow of a cooling-air duct.
 10. The airconditioning system according to claim 3, wherein at least one of saidnozzles is disposed in a region of said air outlet of said evaporatorhousing so that the agent can be injected in a direction of flow of acooling-air duct.
 11. The air conditioning system according to claim 1,further comprising a coupling piece disposed on said supply line forconnecting to a cleaning-agent feed.
 12. The air conditioning systemaccording to claim 1, further comprising: an activatable switchingvalve; and a reservoir for storing the cleaning agent and permanentlyconnected to said supply line through said activatable switching valve.13. The air conditioning system according to claim 12, furthercomprising an electronic control connected to said activatable switchingvalve, said activatable switching valve is actuable one of manually,semiautomatically and fully automatically via said electronic control.14. The air conditioning system according to claim 1, wherein saidinjection device is a retrofit kit for retrofitting existing airconditioning systems.
 15. The air conditioning system according to claim1, wherein the air conditioning system is for use in motor vehicles witha refrigerant conveyed in a closed circuit.